Film and television actor, most widely known for his role in "The West Wing".

In 1990 Spencer joined the cast of the television series "L.A. Law", playing rumpled, pugnacious associate attorney Tommy Mullaney. Spencer's work also extended to video games, portraying the role of Captain Hugh Paulsen in the 1995 video game Wing Commander IV: The Price of Freedom.
From 1999 until his death in 2005, Spencer was cast in the role of White House Chief of Staff Leo McGarry on the NBC political drama series "The West Wing". Both Spencer and his character were recovering alcoholics.